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ASF subversion and git services commented on JENA-1428: ------------------------------------------------------- Commit 3def36360acc0fecb1ce1ff553279e0412c5bc73 in jena's branch refs/heads/master from [~andy.seaborne] [ https://git-wip-us.apache.org/repos/asf?p=jena.git;h=3def363 ] JENA-1428: Add tests > NPE in Query Builder > -------------------- > > Key: JENA-1428 > URL: https://issues.apache.org/jira/browse/JENA-1428 > Project: Apache Jena > Issue Type: Bug > Components: QueryBuilder > Affects Versions: Jena 3.4.0 > Reporter: Claude Warren > Assignee: Claude Warren > Priority: Major > Fix For: Jena 3.6.0 > > > As reported by Chris Dollin on users mailing list: > I was experimenting with the query builder and hit a problem > when I was attempting to construct an Expr. This example: > package com.epimorphics.scratch; > import org.apache.jena.arq.querybuilder.ConstructBuilder; > import org.apache.jena.sparql.expr.E_GreaterThan; > import org.apache.jena.sparql.expr.Expr; > import org.apache.jena.sparql.expr.ExprVar; > import org.apache.jena.sparql.expr.nodevalue.NodeValueInteger; > import org.junit.Test; > public class Example { > @Test public void tryBuilding() { > ConstructBuilder cb = new ConstructBuilder(); > Expr x = new NodeValueInteger(1); > Expr y = new ExprVar("y"); > Expr e = new E_GreaterThan(x, y); > cb.addFilter(e); > System.err.println(cb.buildString()); > } > } > when run fails with a null pointer exception: > java.lang.NullPointerException > at org.apache.jena.arq.querybuilder.rewriters. > AbstractRewriter.changeNode(AbstractRewriter.java:126) > at org.apache.jena.arq.querybuilder.rewriters.NodeValueRewriter.visit( > NodeValueRewriter.java:64) > at org.apache.jena.sparql.expr.nodevalue.NodeValueInteger. > visit(NodeValueInteger.java:78) > at org.apache.jena.arq.querybuilder.rewriters.ExprRewriter.visit( > ExprRewriter.java:127) > at org.apache.jena.sparql.expr.NodeValue.visit(NodeValue.java:1205) > at org.apache.jena.arq.querybuilder.rewriters.ExprRewriter.visit( > ExprRewriter.java:65) > at org.apache.jena.sparql.expr.ExprFunction2.visit( > ExprFunction2.java:109) > at org.apache.jena.arq.querybuilder.rewriters.ElementRewriter.visit( > ElementRewriter.java:70) > at org.apache.jena.sparql.syntax.ElementFilter.visit( > ElementFilter.java:35) > at org.apache.jena.arq.querybuilder.rewriters.ElementRewriter.visit( > ElementRewriter.java:141) > at org.apache.jena.sparql.syntax.ElementGroup.visit( > ElementGroup.java:120) > at org.apache.jena.arq.querybuilder.handlers.WhereHandler.addAll( > WhereHandler.java:81) > at org.apache.jena.arq.querybuilder.handlers.HandlerBlock.addAll( > HandlerBlock.java:218) > at org.apache.jena.arq.querybuilder.handlers.HandlerBlock.addAll( > HandlerBlock.java:245) > at org.apache.jena.arq.querybuilder.AbstractQueryBuilder.build( > AbstractQueryBuilder.java:555) > at org.apache.jena.arq.querybuilder.AbstractQueryBuilder.buildString( > AbstractQueryBuilder.java:522) > at com.epimorphics.scratch.Example.tryBuilding(Example.java:20) > at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) > at sun.reflect.NativeMethodAccessorImpl.invoke( > NativeMethodAccessorImpl.java:62) > at sun.reflect.DelegatingMethodAccessorImpl.invoke( > DelegatingMethodAccessorImpl.java:43) > at java.lang.reflect.Method.invoke(Method.java:498) > at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall( > FrameworkMethod.java:47) > at org.junit.internal.runners.model.ReflectiveCallable.run( > ReflectiveCallable.java:12) > at org.junit.runners.model.FrameworkMethod.invokeExplosively( > FrameworkMethod.java:44) > at org.junit.internal.runners.statements.InvokeMethod. > evaluate(InvokeMethod.java:17) > at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271) > at org.junit.runners.BlockJUnit4ClassRunner.runChild( > BlockJUnit4ClassRunner.java:70) > at org.junit.runners.BlockJUnit4ClassRunner.runChild( > BlockJUnit4ClassRunner.java:50) > at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238) > at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63) > at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236) > at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53) > at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229) > at org.junit.runners.ParentRunner.run(ParentRunner.java:309) > at org.junit.runner.JUnitCore.run(JUnitCore.java:160) > at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs( > JUnit4IdeaTestRunner.java:68) > at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater. > startRunnerWithArgs(IdeaTestRunner.java:47) > at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart( > JUnitStarter.java:242) > at com.intellij.rt.execution.junit.JUnitStarter.main( > JUnitStarter.java:70) > Replacing the addFilter line with > cb.addFilter("1 > ?y"); > does not fail, terminating with the expected print-out > of a construct query > CONSTRUCT > { > } > WHERE > { FILTER ( 1 > ?y )} > I tried poking around with the debugger but couldn't see anyhting > obvious. However, /sometimes/ stepping through the code > results in it working and sometimes not, presumably depending > on exactly when I give up through-stepping. > Am I doing anything obviously wrong (like misunderstanding > how to use the Expr functionality) or should I file a JIRA? > This is Jena 3.4.0. -- This message was sent by Atlassian JIRA (v7.6.3#76005)